Examples (when communicating with someone at your location)
I hope the server comes soon. (The destination is toward you.)
I will go to the airport to pick her up. (The destination is away from your location.)
I would have gone to their open house if I had known about it. (The destination was away from your location.)

Exception: If you are communicating with someone who is at your destination — not your location — use their location to choose the word. Therefore, the word would be come.

Examples (when someone is at your destination)
I will come to your office tomorrow. (The receiver is at your destination.)
I should have come to your open house. (The destination would have been at the receiver’s location.)